We will perform a microscopic study of the choroidal and retinal vessels of cynomolgus monkeys (M. fascicularis) with diet-induced atherosclerosis and of monkeys in which conditions are favorable for regression of atherosclerosis. Serial fluorescent retinal angiography will be performed during the expected progression and regression of atherosclerosis. The angiographic findings will be correlated with microscopic observations in vessels of enucleated eyes as well as with atherosclerosis in other arterial territories.